【摘要】 棕色固氮菌固氮酶钼铁蛋白结晶,经酒石酸解离后得到一个含钢铁小分子组分,与棕色固氮菌突变株uw₄₅无细胞提取液的重组比活为6.8nM Mo natom^-1 min^-1。它是由二种物质组成的混合物,其分子量分别为2100和1850道尔顿,分子量为2100道尔顿的成分含钼铁。酒石酸处理后的沉淀,再用N—甲基甲酰胺抽提得到的含钼铁组分具有恢复突变株uw₄₅乙炔还原活性的能力。经纸层析鉴定与用Shah法制备的铁钼辅因子相类似。由于Shah和Smith法制备的两种铁钼辅因子还原乙炔和氰化钾的比活不同,而且分子量也有大小,说明这两种铁钼辅因子结构可能不尽相同。更多还原

【Abstract】 The Mo-and Fe-Containing component of the active Small molecule obtained from nitrogenase MoFe-protein of Azotobacter Vinelandii by treatment with tartaric acid. Specific activity of it recombined with extr acts from mutant strain uw₄₅ of Azotobacter vinelandi i is 6.8 C₂H₄ nM Mo natom^-1min^-1. It consisted of two components.The molecularweight of they were 2100 and 1850 daltons respectively. The former contained Mo and Fe.The preciptate formed after treatment with tartaric acid was further extracted with N-methylformamide, the component thus obtained which was active is restoring the acetylene reduction activity of extract from mutant strain uw₄₅ of A. vinelandii was show to be similar to the FeMoCo prepared according to the method described by Shah by paper chromatographic determination.Owing to the difference in specific activities for C₂H₂ and KCN reduction and the unequal of molecular weights of FeMoCo prepared according to Shah’s and Smith’s methods the two kinds of FeMoCo are probable distinctive in the molecular structure更多还原